Libero arbitrio e responsabilità morale

The belief in free will has given us both the religious conception of “sin” and our commitment to retributive justice. The U.S. Supreme Court has called free will a “universal and persistent” foundation for our system of law, distinct from “a deterministic view of human conduct that is inconsistent with the underlying precepts of our criminal justice system” (United States v. Grayson, 1978). Any intellectual developments that threatened free will would seem to put the ethics of punishing people for their bad behavior in question.

The great worry, of course, is that an honest discussion of the underlying causes of human behavior appears to leave no room for moral responsibility. If we view people as neuronal weather patterns, how can we coherently speak about right and wrong or good and evil? […]

Happily, we can. What does it mean to take responsibility for an action? […]

Consider the following examples of human violence:

1. A four-year-old boy was playing with his father’s gun and killed a young woman. The gun had been kept loaded and unsecured in a dresser drawer.

2. A 12-year-old boy who had been the victim of continual physical and emotional abuse took his father’s gun and intentionally shot and killed a young woman because she was teasing him.

3. A 25-year-old man who had been the victim of continual abuse as a child intentionally shot and killed his girlfriend because she left him for another man.

4. A 25-year-old man who had been raised by wonderful parents and never abused intentionally shot and killed a young woman he had never met “just for the fun of it.”

5. A 25-year-old man who had been raised by wonderful parents and never abused intentionally shot and killed a young woman he had never met “just for the fun of it.” An MRI of the man’s brain revealed a tumor the size of a golf ball in his medial prefrontal cortex (a region responsible for the control of emotion and behavioral impulses).

In each case a young woman died, and in each case her death was the result of events arising in the brain of another human being. But the degree of moral outrage we feel depends on the background conditions described in each case. We suspect that a four-year-old child cannot truly kill someone on purpose and that the intentions of a 12-year-old do not run as deep as those of an adult. In cases 1 and 2, we know that the brain of the killer has not fully matured and that not all the responsibilities of personhood have yet been conferred. The history of abuse and the precipitating circumstance in case 3 seem to mitigate the man’s guilt: This was a crime of passion committed by a person who had himself suffered at the hands of others. In 4 there has been no abuse, and the motive brands the perpetrator a psychopath. Case 5 involves the same psychopathic behavior and motive, but a brain tumor somehow changes the moral calculus entirely: Given its location, it seems to divest the killer of all responsibility for his crime. And it works this miracle even if the man’s subjective experience was identical to that of the psychopath in case 4—for the moment we understand that his feelings had a physical cause, a brain tumor, we cannot help seeing him as a victim of his own biology.

How can we make sense of these gradations of moral responsibility when brains and their background influences are in every case, and to exactly the same degree, the real cause of a woman’s death?

We need not have any illusions that a causal agent lives within the human mind to recognize that certain people are dangerous. What we condemn most in another person is the conscious intention to do harm. Degrees of guilt can still be judged by reference to the facts of a case: the personality of the accused, his prior offenses, his patterns of association with others, his use of intoxicants, his confessed motives with regard to the victim, etc. If a person’s actions seem to have been entirely out of character, this might influence our view of the risk he now poses to others. If the accused appears unrepentant and eager to kill again, we need entertain no notions of free will to consider him a danger to society.

Why is the conscious decision to do another person harm particularly blameworthy? Because what we do subsequent to conscious planning tends to most fully reflect the global properties of our minds—our beliefs, desires, goals, prejudices, etc. If, after weeks of deliberation, library research, and debate with your friends, you still decide to kill the king—well, then killing the king reflects the sort of person you really are. The point is not that you are the ultimate and independent cause of your actions; the point is that, for whatever reason, you have the mind of a regicide.

Certain criminals must be incarcerated to prevent them from harming other people. The moral justification for this is entirely straightforward: Everyone else will be better off this way. Dispensing with the illusion of free will allows us to focus on the things that matter—assessing risk, protecting innocent people, deterring crime, etc. However, certain moral intuitions begin to relax the moment we take a wider picture of causality into account. Once we recognize that even the most terrifying predators are, in a very real sense, unlucky to be who they are, the logic of hating (as opposed to fearing) them begins to unravel. Once again, even if you believe that every human being harbors an immortal soul, the picture does not change: Anyone born with the soul of a psychopath has been profoundly unlucky.

Why does the brain tumor in case 5 change our view of the situation so dramatically? One reason is that its influence has been visited upon a person who (we must assume) would not otherwise behave in this way. Both the tumor and its effects seem adventitious, and this makes the perpetrator appear to be purely a victim of biology. Of course, if we couldn’t cure his condition, we would still need to lock him up to prevent him from committing further crimes, but we would not hate him or condemn him as evil. Here is one front on which I believe our moral intuitions must change: The more we understand the human mind in causal terms, the harder it becomes to draw a distinction between cases like 4 and 5.

The men and women on death row have some combination of bad genes, bad parents, bad environments, and bad ideas (and the innocent, of course, have supremely bad luck). Which of these quantities, exactly, were they responsible for? No human being is responsible for his genes or his upbringing, yet we have every reason to believe that these factors determine his character. Our system of justice should reflect an understanding that any of us could have been dealt a very different hand in life. In fact, it seems immoral not to recognize just how much luck is involved in morality itself.

[…]

Despite our attachment to the notion of free will, most of us know that disorders of the brain can trump the best intentions of the mind. This shift in understanding represents progress toward a deeper, more consistent, and more compassionate view of our common humanity—and we should note that this is progress away from religious metaphysics. Few concepts have offered greater scope for human cruelty than the idea of an immortal soul that stands independent of all material influences, ranging from genes to economic systems. Within a religious framework, a belief in free will supports the notion of sin—which seems to justify not only harsh punishment in this life but eternal punishment in the next. And yet, ironically, one of the fears attending our progress in science is that a more complete understanding of ourselves will dehumanize us.

Viewing human beings as natural phenomena need not damage our system of criminal justice. If we could incarcerate earthquakes and hurricanes for their crimes, we would build prisons for them as well. We fight emerging epidemics—and even the occasional wild animal—without attributing free will to them. Clearly, we can respond intelligently to the threat posed by dangerous people without lying to ourselves about the ultimate origins of human behavior. We will still need a criminal justice system that attempts to accurately assess guilt and innocence along with the future risks that the guilty pose to society. But the logic of punishing people will come undone—unless we find that punishment is an essential component of deterrence or rehabilitation.

It must be admitted, however, that the issue of retribution is a tricky one. In a fascinating article in The New Yorker, Jared Diamond writes of the high price we sometimes pay when our desire for vengeance goes unfulfilled. He compares the experiences of two people: his friend Daniel, a New Guinea highlander who avenged the death of a paternal uncle; and his late father-in-law, who had the opportunity to kill the man who murdered his entire family during the Holocaust but opted instead to turn him over to the police. (After spending only a year in jail, the killer was released.) The consequences of taking revenge in the first case and for-going it in the second could not have been starker. While there is much to be said against the vendetta culture of the New Guinea highlands, Daniel’s revenge brought him exquisite relief. Whereas Diamond’s father-in-law spent the last 60 years of his life “tormented by regret and guilt.” Clearly, vengeance answers to a powerful psychological need in many of us.

We are deeply disposed to perceive people as the authors of their actions, to hold them responsible for the wrongs they do us, and to feel that these transgressions must be punished. Often, the only punishment that seems appropriate is for the perpetrator of a crime to suffer or forfeit his life. It remains to be seen how a scientifically informed system of justice might steward these impulses. Clearly, a full account of the causes of human behavior should attenuate our natural response to injustice, at least to some degree. I doubt, for instance, that Diamond’s father-in-law would have suffered the same anguish if his family had been trampled by an elephant or laid low by cholera. Similarly, we can assume that his regret would have been significantly eased if he had learned that his family’s killer had lived a flawlessly moral life until a virus began ravaging his medial pre-frontal cortex.

However, it may be that a sham form of retribution would still be moral—even necessary—if it led people to behave better than they otherwise would. Whether it is useful to emphasize the punishment of certain criminals—rather than their containment or rehabilitation—is a question for social and psychological science. But it seems clear that a desire for retribution, arising from the idea that each person is the free author of his thoughts and actions, rests on a cognitive and emotional illusion—and perpetuates a moral one.